THE MUSCLES. 



5G1 



Involuntary Muscle. The same substances are found in plain 

 muscle as in striated muscle, except that plain muscle contains six 



Fig. 205. Ergographic Curve of a Case of Addison's Disease, Show- 

 ing Rapid Exhaustion of Muscle. (LANGLOis.) 



Read from right. 



times more neucleoproteid than striped muscle. In its contraction the 

 latent period is about a second, and the contraction lasts several sec- 



Fig. 206. Fick's Work Adder. (LAULANifi.) 



The wheel (rf) bears upon its axle a counterpoised muscle lever (c), ending 

 in a pawl (m), through which the wheel is caused to revolve when the lever is 

 pulled upward by the attached muscle. A second pawl (n) prevents the wheel 

 from turning back when the muscle relaxes. On the other side the axle of the 

 wheel bears a pulley from which a weight (d) is suspended. The turning of the 

 wheel winds the suspending cord upon the pulley and raises the weight ((?). 

 The muscle preparation should be the double adductor, suggested by Fick. 



ids; it spreads as a wave from fiber to fiber. Its irritability is 

 dependent upon temperature; heat decreases its tonus, cold 



.30 



